Cardiac arrest claims over 450,000 lives per year in the United States alone. There is a high incidence of neurological complications amongst survivors, and these represent the leading cause of morbidity. Over the past several years, the care of these patients has been improved via the introduction of new systemic as well as neurospecific therapies. Speed of institution of therapy appears to be an important factor affecting efficacy. Yet, in the crucial initial hours to days post-arrest, assessment of neurological status in these patients is essentially non-existent. Thus, there is a need for an objective validated tool to assess prognosis and to track neurological status in the early recovery period. In response to this need, we have developed the Cortical Health Index (CHI). This EEG-based index incorporates multiple weighted parameters which are related to cortical recovery. The strength and uniqueness of this approach results from consideration of both the temporal as well as the spectral domains. Our Phase II results demonstrate that CHI measured within the first 6-hours post-arrest is strongly correlated with clinical outcome at hospital discharge in a 30-patient cardiac arrest study. We now propose to pursue regulatory approval of the CHI Monitor. Our plan involves a prospective clinical trial involving 4 centers and 100 patients. We will test the ability of CHI to 1) predict subsequent neurological functional outcome of cardiac arrest patients, and 2) provide real-time tracking of brain injury and response to therapy. Successful completion of this project is defined by FDA clearance of the CHI Monitor. It is our goal that the CHI Monitor will identify patients who could benefit from aggressive intervention, and then track the response to the therapy. Providing this information to the treating cardiologist in the immediate post-resuscitation period represents a major change in care delivery for the cardiac arrest survivor. [unreadable] [unreadable] [unreadable]